The present invention relates to a method of manufacturing a masked semiconductor laser that can be used as a light source for an optical memory, a magnetooptic memory, or the like.
Recording of information at high packing density has been made possible in recent years by optical memories and magnetooptic memories. Technical trends, however, are toward recording and reproducing of information at higher packing density. For reading recorded information from pits which are 0.4 to 0.5 micron across on an optical disk, it is necessary to reduce the diameter of a reading light beam to that range. With semiconductor lasers and imaging optical means which are presently available, however, it is highly difficult to reduce the diameter of an emitted laser beam to a range smaller than the wavelength of the laser beam, e.g., about 0.8 micron because of diffraction limitations.